Epidemiology of ventilator-associated pneumonia in a long-term acute care hospital

Ventilator-associated pneumonia in patients on prolonged mechanical ventilation: description, risk factors for mortality, and performance of the SOFA score

Objective:

Ventilator-associated pneumonia (VAP) is a serious complication of mechanical ventilation (MV). However, data on VAP in patients on prolonged MV (PMV) are scarce. We aimed to describe the characteristics of VAP patients on PMV and to identify factors associated with mortality.

Methods:

This was a retrospective cohort study including VAP patients on PMV. We recorded baseline characteristics, as well as 30-day and 90-day mortality rates. Variables associated with mortality were determined by Kaplan-Meier survival analysis and Cox regression model.

Results:

We identified 80 episodes of VAP in 62 subjects on PMV. The medians for age, Charlson Comorbidity Index, SOFA score, and days on MV were, respectively, 69.5 years, 5, 4, and 56 days. Episodes of VAP occurred between days 21 and 50 of MV in 28 patients (45.2%) and, by day 90 of MV, in 48 patients (77.4%). The 30-day and 90-day mortality rates were 30.0% and 63.7%, respectively. There were associations of 30-day mortality with the SOFA score (hazard ratio [HR] = 1.30; 95% CI: 1.12-1.52; p < 0.001) and use of vasoactive agents (HR = 4.0; 95% CI: 1.2-12.9; p = 0.02), whereas 90-day mortality was associated with age (HR = 1.03; 95% CI: 1.00-1.05; p = 0.003), SOFA score (HR = 1.20; 95% CI: 1.07-1.34; p = 0.001), use of vasoactive agents (HR = 4.07; 95% CI: 1.93-8.55; p < 0.001), and COPD (HR = 3.35; 95% CI: 1.71-6.60; p < 0.001).

Conclusions:

Mortality rates in VAP patients on PMV are considerably high. The onset of VAP can occur various days after MV initiation. The SOFA score is useful for predicting fatal outcomes. The factors associated with mortality could help guide therapeutic decisions and determine prognosis.

Effects of nurse-led sedation protocols on mechanically ventilated intensive care adults: A systematic review and meta-analysis

OBJECTIVES

The objective of the study was to compare nurse-led sedation protocols with physician-led usual care in intensive care units (ICUs) in treating mechanically ventilated adult patients.

REVIEW METHOD USED

This is a systematic review and meta-analysis.

DATA SOURCES

PubMed, Cochrane Library, EMBASE, CINAHL, China National Knowledge Infrastructure, and China Wanfang databases were interrogated for articles published before May 2020.

REVIEW METHOD

As per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, eight randomised controlled trials (RCTs) and six preintervention and postintervention studies published in English and Chinese met the inclusion criteria for the meta-analysis. Two reviewers independently extracted data into a tabular format using predefined data fields. Disagreements were resolved by consensus. The quality of the included RCTs and preintervention and postintervention studies was assessed using the Cochrane Quality Assessment Tool and Risk Of Bias In Non-randomised Studies of Interventions assessment tool.

RESULTS

Eight RCTs were of intermediate methodological quality, and six preintervention and postintervention studies exhibited a low to moderate risk of bias. Compared with usual care, nurse-led sedation protocols resulted in significantly decreased durations of mechanical ventilation (days) (standardised mean difference = -1.765; 95% confidence interval [CI] = -2.461, -1.068); P < 0.001; I² = 97.7%); decreased length of ICU stay (days) (standardised mean difference = -1.463; 95% CI = -2.181, -0.745; P < 0.001; I² = 97.3%); reduced ICU mortality (relative risk [RR] = 0.854; 95% CI = 0.747, 0.983; P = 0.027), I² = 0%); and decreased incidence of ventilator-associated pneumonia (RR = 0.438; 95% CI = 0.292, 0.657; P < 0.001; I² = 41.4%), delirium (RR = 0.522; 95% CI = 0.338, 0.807; P = 0.003; I² = 26.6%), and extubation failure (RR = 0.498; 95% CI = 0.266, 0.932; P = 0.029; I² = 45.1%).

CONCLUSIONS

Although pre-post intervention study design cannot establish causality, the present findings raise the considerable possibility that a sedation protocol can be safely implemented by nurses to reduce mortality in ICUs and sedation-related adverse events in patients on mechanical ventilation compared with physician-led usual care.

Pathogenesis-Targeted Preventive Strategies for Multidrug Resistant Ventilator-Associated Pneumonia: A Narrative Review

Ventilator-associated pneumonia (VAP) is the most common hospital-acquired infection in the intensive care unit (ICU), accounting for relevant morbidity and mortality among critically ill patients, especially when caused by multidrug resistant (MDR) organisms. The rising problem of MDR etiologies, which has led to a reduction in treatment options, have increased clinician’s attention to the employment of effective prevention strategies. In this narrative review we summarized the evidence resulting from 27 original articles that were identified through a systematic database search of the last 15 years, focusing on several pathogenesis-targeted strategies which could help preventing MDR-VAP. Oral hygiene with Chlorhexidine (CHX), CHX body washing, selective oral decontamination (SOD) and/or digestive decontamination (SDD), multiple decontamination regimens, probiotics, subglottic secretions drainage (SSD), special cuff material and shape, silver-coated endotracheal tubes (ETTs), universal use of gloves and contact isolation, alcohol-based hand gel, vaporized hydrogen peroxide, and bundles of care have been addressed. The most convincing evidence came from interventions directly addressed against the key factors of MDR-VAP pathogenesis, especially when they are jointly implemented into bundles. Further research, however, is warranted to identify the most effective combination.

Use of Chlorhexidine to Prevent Ventilator-Associated Pneumonia in a Long-term Care Setting: A Retrospective Medical Record Review

BACKGROUND

The purpose of this study was to explore the use of the oral decontamination solution chlorhexidine (CHX) to reduce ventilator-associated pneumonia (VAP) in a long-term ventilator care setting over time. Most of the research in this area has been conducted in acute and intensive care settings.

METHODS

This study was a retrospective medical record review conducted in a long-term care facility with a dedicated ventilator unit. Veterans records (N = 12) were accessed for this study. The study covered 50 months, with a 43-month time period during which CHX was administered.

RESULTS

While the sample size was small, many of the veterans on ventilators used CHX for years without an incident of VAP.

CONCLUSIONS

These findings support using CHX to significantly reduce the number of days of intravenous antibiotics used to treat VAP with little side effects.

Diagnostic Efficacy of Serum Amyloid A Protein and Soluble Intercellular Adhesion Molecule 1 in Pediatric Ventilator-Associated Pneumonia

Objectives:

Study of inflammatory biomarkers which may aid in early detection of ventilator-associated pneumonia (VAP) in children and predicting their outcome.

Patients:

Thirty-five children, aged 2 months to 13 years, needed mechanical ventilation (MV) for more than 48 hours due to causes other than pneumonia.

Methods:

Measurement of serum amyloid A (SAA) protein, soluble intercellular adhesion molecule 1 (sICAM-1), and C-reactive protein (CRP), modified clinical pulmonary infection score (CPIS) and performing culture of endotracheal aspirate at the start and on the third day of MV.

Results:

Ventilator-associated pneumonia was diagnosed by CPIS in 6 (17.1%) of 35 patients. On the third day of MV, there was a significant increase in serum mean levels of SAA, sICAM-1, and CRP in comparison to the start of MV ( P = .005, .004, and .01, respectively). Three (50%) of 6 patients with VAP died, while 4 (14.28%) of 28 patients without VAP died. The sensitivity of serum SAA, sICAM-1, and CPIS were 100% for predicting VAP, while specificity was highest for CPIS (96.55%) followed by SAA (93.1%). Combination of CPIS and SAA increased the specificity to 100%. For predicting nonsurvival, serum SAA and sICAM-1 had a sensitivity of 100% and a specificity of 92.86% and 89.29%, respectively.

Conclusion:

Serum amyloid A and sICAM-1 may be considered as reliable markers for detection of VAP. Combination of serum SAA with CPIS increased the specificity to 100%. Measurement of SAA in patients with VAP also had a good predictive value for nonsurvival in such patients.

Incidence, bacteriology, and clinical outcome of ventilator-associated pneumonia at tertiary care hospital

Background:

Ventilator-associated pneumonia (VAP) is the most frequent Intensive Care Unit acquired infection.

Aims:

The aim is to determine the incidence, bacteriology and factors affecting VAP and to determine the multi-drug resistant (MDR) pathogens.

Settings and Design:

This was a prospective observational study conducted over a period of 1 year from April 1, 2011, to March 31, 2012.

Materials and Methods:

The patients fulfilling criteria of VAP were included in this study.

Statistical Analysis:

This was performed using SPSS trial version 11.0 software (SPSS Inc., Chicago, Illinois, USA) and the values of P < 0.05 were considered statistically significant.

Results:

Totally 74 (27.71%) patients were developed VAP. Of total 74 patients with VAP 53 (71.62%) were females and 21 (28.37%) were females (P < 0.0001). Total 13 (17.56%) patients had early-onset VAP and 61 (82.43%) had late-onset VAP (P < 0.0001). The overall incidence of VAP rate per 1000 ventilator days was 39.59. Total 126 bacterial isolates found in 74 patients with VAP. Predominant isolates were Gram-negative 52 (70.27%). Total 41 (55.40%) patients had polymicrobial VAP, and 33 (44.59%) had single isolate. Total 55 (43.65%) isolates were MDR organisms. Total 22 patients with VAP succumbed during treatment with overall case fatality rate of 29.72%. Of total 55 MDR isolates in VAP, 13 (26.63%) were Klebsiella spp., 11(20%) Pseudomonas aeruginosa, 14 (25.45%) Acinetobacter, 8 (14.54%) Escherichia coli, and 9 (16.36%) coagulase positive Staphylococcus aureus. Total 12 (21.41%) patients succumbed among MDR isolates.

Conclusions:

There was a high incidence of MDR pathogens in late-onset VAP. The Gram-negative organisms Klebsiella, PseudomonasE. coli and Acinetobacter were the most commonly isolated organisms with high mortality rates.

Staphylococcus aureus α toxin potentiates opportunistic bacterial lung infections

Broad-spectrum antibiotic use may adversely affect a patient's beneficial microbiome and fuel cross-species spread of drug resistance. Although alternative pathogen-specific approaches are rationally justified, a major concern for this precision medicine strategy is that co-colonizing or co-infecting opportunistic bacteria may still cause serious disease. In a mixed-pathogen lung infection model, we find that the Staphylococcus aureus virulence factor α toxin potentiates Gram-negative bacterial proliferation, systemic spread, and lethality by preventing acidification of bacteria-containing macrophage phagosomes, thereby reducing effective killing of both S. aureus and Gram-negative bacteria. Prophylaxis or early treatment with a single α toxin neutralizing monoclonal antibody prevented proliferation of co-infecting Gram-negative pathogens and lethality while also promoting S. aureus clearance. These studies suggest that some pathogen-specific, antibody-based approaches may also work to reduce infection risk in patients colonized or co-infected with S. aureus and disparate drug-resistant Gram-negative bacterial opportunists.

High-intensity meropenem combinations with polymyxin B: new strategies to overcome carbapenem resistance in Acinetobacter baumannii

OBJECTIVES

The pharmacodynamics of polymyxin/carbapenem combinations against carbapenem-resistant Acinetobacter baumannii (CRAB) are largely unknown. Our objective was to determine whether intensified meropenem regimens in combination with polymyxin B enhance killing and resistance suppression of CRAB.

METHODS

Time-kill experiments for meropenem and polymyxin B combinations were conducted against three polymyxin B-susceptible (MIC of polymyxin B = 0.5 mg/L) CRAB strains with varying meropenem MICs (ATCC 19606, N16870 and 03-149-1; MIC of meropenem = 4, 16 and 64 mg/L, respectively) at 10⁸ cfu/mL. A hollow-fibre infection model was then used to simulate humanized regimens of polymyxin B and meropenem (2, 4, 6 and 8 g prolonged infusions every 8 h) versus N16870 at 10⁸ cfu/mL over 14 days. New mathematical mechanism-based models were developed using S-ADAPT.

RESULTS

Time-kill experiments were well described by the mathematical mechanism-based models, with the presence of polymyxin B drastically decreasing the meropenem concentration needed for half-maximal activity against meropenem-resistant populations from 438 to 82.1 (ATCC 19606), 158 to 93.6 (N16870) and 433 to 76.0 mg/L (03-149-1). The maximum killing effect of combination treatment was similar among all three strains despite divergent meropenem MIC values (E_max = 2.13, 2.08 and 2.15; MIC of meropenem = 4, 16 and 64 mg/L, respectively). Escalating the dose of meropenem in hollow-fibre combination regimens from 2 g every 8 h to 8 g every 8 h resulted in killing that progressed from a >2.5 log₁₀ cfu/mL reduction with regrowth by 72 h (2 g every 8 h) to complete eradication by 336 h (8 g every 8 h).

CONCLUSION

Intensified meropenem dosing in combination with polymyxin B may offer a unique strategy to kill CRAB irrespective of the meropenem MIC.

The effectiveness of a bundle in the prevention of ventilator-associated pneumonia

Objectives

The aim of this study was to evaluate the impact of a bundle called FAST HUG in ventilator-associated pneumonia, weigh the healthcare costs of ventilator-associated pneumonia patients in the intensive care unit, and hospital mortality due to ventilator-associated pneumonia.

Material and methods

The study was performed in a private hospital that has an 8-bed intensive care unit. It was divided into two phases: before implementing FAST HUG, from August 2011 to August 2012 and after the implementation of FAST HUG, from September 2012 to December 2013. An individual form for each patient in the study was filled out by using information taken electronically from the hospital medical records. The following data was obtained from each patient: age, gender, reason for hospitalization, use of three or more antibiotics, length of stay, intubation time, and outcome.

Results

After the implementation of FAST HUG, there was an observable decrease in the occurrence of ventilator-associated pneumonia (p < 0.01), as well as a reduction in mortality rates (p < 0.01). In addition, the intervention resulted in a significant reduction in intensive care unit hospital costs (p < 0.05).

Conclusion

The implementation of FAST HUG reduced the number of ventilator-associated pneumonia cases. Thus, decreasing costs, reducing mortality rates and length of stay, which therefore resulted in an improvement to the overall quality of care.

Intervention to Reduce Ventilator-Associated Pneumonia in Individuals on Long-Term Ventilation by Introducing a Customized Bundle

OBJECTIVES

To evaluate the effectiveness of a modified bundle of preventative measures to decrease ventilator-associated pneumonia (VAP) in chronically ventilated long-term care facility (LTCF) residents.

DESIGN

Cohort before-and-after study.

SETTING

Geriatric hospital ward.

PARTICIPANTS

LTCF residents on long-term ventilation.

INTERVENTION

The modified bundle included hand hygiene before patient care, elevation of the head of the bed to more than 30° for individuals who are supine, chlorhexidine oral care at the beginning of each nursing shift, keeping tracheostomy cannula balloon pressure at 20 to 30 cm H2 O, and measuring nasogastric food remnants before every meal for individuals fed through a nasogastric tube.

MEASUREMENTS

Number of VAP episodes was determined prospectively, and rates were calculated as episodes per 1,000 ventilation days.

RESULTS

VAP rate decreased from 5.97 before the intervention to 2.34 after the intervention (P < .001). The use of broad-spectrum antibiotics decreased from 1,788 defined daily doses before the intervention to 1,093 after (P = .04).

CONCLUSION

A modified bundle successfully decreased VAP rates in chronically ventilated elderly LTCF residents.

Device-related infections in long-term healthcare facilities: the challenge of prevention

The world is aging and the number of elderly multimorbid patients is steadily increasing. The limited numbers of acute care beds in hospitals, in addition to the need to reduce costs, has led to the introduction of efficient discharge policies, which in turn have increased demand for beds in nursing homes and long-term care facilities (LTCFs). As a consequence, the number of postacute LTCF residents is rising, as is the number of residents requiring complex medical care delivered by use of indwelling medical devices. These devices place patients at a heightened risk for infection. Furthermore, infection control resources in LTCFs are often limited. This article reviews the preventive measures that should be taken in LTCFs to reduce the risk of device-related infections.

Outcomes of a ventilator-associated pneumonia bundle on rates of ventilator-associated pneumonia and other health care-associated infections in a long-term acute care hospital setting

Long-term trends in ventilator-associated pneumonia (VAP) rates, and other health care-associated infections, were examined prior to, during, and after introduction of a VAP bundle in a long-term acute care hospital setting. VAP incidence rate declined in a step-wise fashion and reached a null value. Incidence rates of bacteremia from any cause declined in a similar fashion. The incidence rates of vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus colonization or infection rates also decreased, but that of Clostridium difficile infection did not. VAP in the long-term acute care hospital setting can be controlled over time with implementation of Centers for Disease Control and Prevention-based VAP bundle. This outcome also may decrease certain other health care-associated infections.

Device-associated infection rates, device utilization, and antimicrobial resistance in long-term acute care hospitals reporting to the National Healthcare Safety Network, 2010

OBJECTIVE

To evaluate national data on healthcare-associated infections (HAIs), device utilization, and antimicrobial resistance in long-term acute care hospitals (LTACHs).

DESIGN AND SETTING

Comparison of data from LTACHs and from medical and medical-surgical intensive care units (ICUs) in short-stay acute care hospitals reporting to the National Healthcare Safety Network (NHSN) during 2010.

METHODS

Rates of central line-associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTIs), and ventilator-associated pneumonia (VAP) as well as device utilization ratios were calculated. For each HAI, pathogen profiles and antimicrobial resistance prevalence were evaluated. Comparisons were made using Poisson regression and the mood median and χ2 tests.

RESULTS

In 2010, 104 LTACHs reported CLABSIs and 57 reported CAUTIs and VAP to the NHSN. Median CLABSI rates in LTACHs (1.25 events per 1,000 device-days reported; range, 0.0-5.96) were comparable to rates in major teaching ICUs and were higher than those in other ICUs. CAUTI rates in LTACHs (median, 2.61; range, 0.0-9.92) were higher and VAP rates (median, 0.0; range, 0.0-3.29) were generally lower than those in ICUs. Central line utilization in LTACHs was higher than that in ICUs, whereas urinary catheter and ventilator utilization was lower. Methicillin resistance among Staphylococcus aureus CLABSIs (83%) and vancomycin resistance among Enterococcus faecalis CAUTIs (44%) were higher in LTACHs than in ICUs. Multidrug resistance among Pseudomonas aeruginosa CAUTIs (25%) was higher in LTACHs than in most ICUs.

CONCLUSIONS

CLABSIs and CAUTIs associated with multidrug-resistant organisms present a challenge in LTACHs. Continued HAI surveillance with pathogen-level data can guide prevention efforts in LTACHs.

Factors predicting ventilator dependence in patients with ventilator-associated pneumonia

Objectives. To determine risk factors associated with ventilator dependence in patients with ventilator-associated pneumonia (VAP). Study Design. A retrospective study was conducted at Chang Gung Memorial Hospital, Kaohsiung, from January 1, 2007 to January 31, 2008. Methods. This study evaluated 163 adult patients (aged ≥18 years). Eligibility was evaluated according to the criterion for VAP, Sequential Organ Failure Assessment (SOFA) score, Acute Physiological Assessment and Chronic Health Evaluation II (APACHE II) score. Oxygenation index, underlying comorbidities, septic shock status, previous tracheostomy status, and factors related to pneumonia were collected for analysis. Results. Of the 163 VAP patients in the study, 90 patients survived, yielding a mortality rate of 44.8%. Among the 90 surviving patients, only 36 (40%) had been weaned off ventilators at the time of discharge. Multivariate logistic regression analysis was used to identify underlying factors such as congestive cardiac failure (P = 0.009), initial high oxygenation index value (P = 0.04), increased SOFA scores (P = 0.01), and increased APACHE II scores (P = 0.02) as independent predictors of ventilator dependence. Results from the Kaplan-Meier method indicate that initial therapy with antibiotics could increase the ventilator weaning rate (log Rank test, P < 0.001). Conclusions. Preexisting cardiopulmonary function, high APACHE II and SOFA scores, and high oxygenation index were the strongest predictors of ventilator dependence. Initial empiric antibiotic treatment can improve ventilator weaning rates at the time of discharge.

Medical device-associated infections in the long-term care setting

Indwelling medical devices are increasingly used in long-term care facilities (LTCFs). These devices place residents at a heightened risk for infection and colonization and infection with multidrug-resistant organisms. Understanding the risk and pathogenesis of infection associated with commonly used medical devices can help facilitate appropriate therapy. Programs to minimize unnecessary use of indwelling medical devices in residents and maximize staff adherence to infection control and maintenance procedures are essential features of a LTCF infection prevention program. LTCFs that provide care for large numbers of residents with indwelling medical devices should routinely perform surveillance for device-related infections and develop systems for assessing the safety and efficacy of newly introduced device-related technology.

Long-term medical utilization following ventilator-associated pneumonia in acute stroke and traumatic brain injury patients: a case-control study

BACKGROUND

The economic burden of ventilator-associated pneumonia (VAP) during the index hospitalization has been confirmed in previous studies. However, the long-term economic impact is still unclear. The aim of this study is to examine the effect of VAP on medical utilization in the long term.

METHODS

This is a retrospective case-control study. Study subjects were patients experiencing their first traumatic brain injury, acute hemorrhagic stroke, or acute ischemic stroke during 2004. All subjects underwent endotracheal intubation in the emergency room (ER) on the day of admission or the day before admission, were transferred to the intensive care unit (ICU) and were mechanically ventilated for 48 hours or more. A total of 943 patients who developed VAP were included as the case group, and each was matched with two control patients without VAP by age ( ± 2 years), gender, diagnosis, date of admission ( ± 1 month) and hospital size, resulting in a total of 2,802 patients in the study. Using robust regression and Poisson regression models we examined the effect of VAP on medical utilization including hospitalization expenses, outpatient expenses, total medical expenses, number of ER visits, number of readmissions, number of hospitalization days and number of ICU days, during the index hospitalization and during the following 2-year period.

RESULTS

Patients in the VAP group had higher hospitalization expenses, longer length of stay in hospital and in ICU, and a greater number of readmissions than the control group patients.

CONCLUSIONS

VAP has a significant impact on medical expenses and utilization, both during the index hospitalization during which VAP developed and in the longer term.

Multidisciplinary trauma intensive care unit checklist: impact on infection rates

The purpose of this study was to implement a multidisciplinary daily quality checklist in a trauma intensive care setting to determine adherence to infection prevention protocols as well as the impact on infection and complications.

METHODS

A multidisciplinary team developed a checklist incorporating evidence-based practice guidelines for the prevention of hospital-acquired infections. Infection rates were monitored and correlated with checklist completion.

RESULTS

Central line, urinary tract infections, and ventilator-associated pneumonia decreased during the study period by 100%, 26%, and 82%, respectively.

CONCLUSION

Initiation of a multidisciplinary daily quality checklist is correlated with decreased infection rates in a trauma intensive care setting.

Severe hospital-acquired pneumonia: a review for clinicians

Hospital-acquired pneumonia (HAP) is one of the most commonly encountered nosocomial infections. Patients who develop severe HAP experience considerable morbidity and mortality, and the condition results in a substantial expenditure of health care resources. A large body of scientific literature about HAP now exists. This article summarizes the current state of knowledge concerning severe HAP with an emphasis on recent advances in its diagnosis, treatment, and prevention.